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Thunderbird only uses TLSv1 regardless of security.tls.version.min/max Settings

SuMo Bot

Versions: Thunderbird 68 and 78, Windows 10

The admin disables TLSv1 at the mail server and with both thunderbird versions fetching and sending mail causes a TLS negotiation error. SSL/TLS or STARTTLS, any authtentification method: All combinations do not work.

The security config ist by default, meaning security.tls.version.min = 3 and security.tls.version.max = 4. But if i monitor the connection with wireshark always the connection is TLSv1 is used, even if i modify the security.tls settings.

What can i do to force thunderbird to use more newer TLS versions?

Versions: Thunderbird 68 and 78, Windows 10 The admin disables TLSv1 at the mail server and with both thunderbird versions fetching and sending mail causes a TLS negotiation error. SSL/TLS or STARTTLS, any authtentification method: All combinations do not work. The security config ist by default, meaning security.tls.version.min = 3 and security.tls.version.max = 4. But if i monitor the connection with wireshark always the connection is TLSv1 is used, even if i modify the security.tls settings. What can i do to force thunderbird to use more newer TLS versions?

All Replies (1)

Solution was found:

The admin changed the TLS cipher suites at the mail server after calling him. After that Thunderbird uses automatically TLSv1.2.

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